The regulator announced in September that it had opened a ‘class inquiry’ into 12 charities with last-known annual incomes of £500,000 or more that had accounts outstanding for at least two of the past five years. Of these organisations, nine have since filed accounts.

It has today broadened the inquiry to include 12 charities with annual incomes between £250,000 and £500,000 that have failed to file accounts for two or more of the past five years.

They include the Muslim Cultural Society of Birmingham and the National Patients Support Trust, which both have accounts that are more than 1,000 days late, and the Michael Davies Charitable Settlement, which lists its activities as "general charitable purposes" on the Charity Commission’s website and also has accounts that are more than 1,000 days late.

The Charity Commission originally identified 71 ‘double default’ charities, but only pursued inquiries into 12 because the others had either ceased to exist or were going into liquidation or administration, were already subject to existing compliance cases, or agreed to file their documents before the inquiry started.

Failure to file accounts with the commission is a criminal offence, and trustees risk prosecution if they do not comply, the commission said.

Sam Younger, chief executive of the commission, said that trustees who do not file accounts show "contempt for the public they are accountable to".

The commission has also today published inquiry reports into five of the original 12 charities.

These reports show the commission ordered the trustees of two charities – The Bridge (Oxford) and the Grace Church Christian Centre – to prepare and submit missing information, and issued an order to obtain bank records and financial information for these two charities. The other three charities, all of which had Bournemouth Borough Council as a corporate trustee, complied without needing direction.

The three charities in the first tranche that have still not filed accounts are the Yad Vochessed Association, the Achiezer Association, and Beighton Welfare Recreation Ground.

Younger said: "The message to trustees from the reports we have published today is simple; submitting this information is your responsibility, even if you delegate it to charity staff or your accountants to do.

"If trustees before you have failed, it is your duty to make good on the default.

"As I have said, we will not tolerate charities that demonstrate contempt for the public they are accountable to by failing to meet reporting requirements. We are continuing to target double defaulting charities and we will pursue these breaches of duty."

The commission said it planned to extend its investigation into double defaulters below £250,000, but has not said when the next tranche will occur or how many charities are likely to be investigated.

The 12 charities added to the investigation announced today are:

Achiezer

Cymmer Workmens Hall and Institute

Markazul Uloom

African Families Support Services

Jamiat-Ul-Muslemeen Quwat-Ul-Islam Masjed

The Parochial Church Council of the Ecclesiastical Parish of St Peter, Notting Hill

Michael Davies Charitable Settlement

Crawley Islamic Centre and Mosque

Muslim Cultural Society of Birmingham

Life Line Missions

The National Patients Support Trust

Hadley Playing Fields and Recreation Ground

The commission said that the parochial church council of St Peter has since filed accounts and had been removed from the inquiry.

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